A lifecycle cost model considering both component and system burn-in for operationally unrepairable systems

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kah How Teo ◽  
Kang Tai ◽  
Vincenzo Schena ◽  
Luca Simonini
Keyword(s):  
System Reliability ◽  
Cost Model ◽  
Cost Savings ◽  
Large System ◽  
Content Type ◽  
Small Satellites ◽  
Procedure Cost ◽  
Warranty Costs ◽  
Final System ◽  
Minimum System

PurposeThis study presents a lifecycle cost model considering multi-level burn-in for operationally unrepairable systems including assembly and warranty costs. A numerical method to obtain system reliability under component replacement during burn-in is also presented with derived error bounds.Design/methodology/approachThe final system reliability after component and system burn-in is obtained and warranty costs are computed. On failure during operation, the system is replaced with another that undergoes an identical burn-in procedure. Cost behaviours for a small and large system are shown in a numerical example.FindingsThere are more cost savings when system burn-in is conducted for a large system whereas a strategy focusing on component burn-in only can also result in cost savings for small systems. In addition, a minimum system burn-in duration is required before cost savings are achieved for these operationally unrepairable systems.Originality/valueThe operationally unrepairable system is a niche class of systems which small satellites fall under and no such study has been conducted before. The authors present a different approach towards the testing of small satellites for a constellation mission.

Cost assessment of multi-tenancy for a 5G broadband network in a dense urban area

2020 ◽  
Vol 22 (2) ◽  
pp. 53-70
Author(s):  
Juan Rendon Schneir ◽  
Konstantinos Konstantinou ◽  
Julie Bradford ◽  
Gerd Zimmermann ◽  
Heinz Droste ◽  
...  
Keyword(s):  
Cost Model ◽  
Access Network ◽  
Cost Savings ◽  
Economic Benefits ◽  
Mobile Service ◽  
Content Type ◽  
Broadband Network ◽  
Cost Implications ◽  
The Cost ◽  
Network Sharing

Purpose 5G systems will enable an improved transmission performance and the delivery of advanced communication services. To meet the expected requirements, operators will need to invest in network modernisation, with the radio access network being the most expensive network component. One possible way for operators to reduce this investment would be via sharing of resources by means of a multi-tenancy concept. This implies that a mobile service provider may use the common infrastructure of one or various infrastructure providers, whereby it provides services to multiple tenants. This paper aims to study the expected cost savings in terms of capital expenditures (CAPEX) and operational expenditures (OPEX) that can be achieved when using a cloudified 5G multi-tenant network. Design/methodology/approach A cost model was used. The study period is 2020-2030 and the study area consists of three local districts in central London, UK. Findings This paper describes that the total cost reduction achieved when using multi-tenancy for a 5G broadband network in comparison with the case where operators make the investment independently ranges from 5.2% to 15.5%. Research limitations/implications Further research is needed to assess the cost implications of network sharing for 5G on a regional or nationwide basis. Originality/value Very little quantitative research about the cost implications of network sharing under 5G networks has been published so far. This paper sheds light on the economic benefits of multi-tenancy in a 5G broadband network.

scholarly journals Telecommunication Systems for Small Satellites Operating at High Frequencies: A Review

Information ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 258
Author(s):  
Alessandra Babuscia
Keyword(s):  
New Technologies ◽  
Cost Savings ◽  
Low Earth Orbit ◽  
Lessons Learned ◽  
Small Satellite ◽  
High Frequencies ◽  
Small Satellites ◽  
Telecommunication Systems ◽  
X Band ◽  
Final System

Small Satellites and in particular CubeSats are becoming extremely popular platforms with which to perform space research. They allow for rapid prototyping with considerable cost savings with respect to traditional missions. However, as small satellite missions become more ambitious in terms of destinations to reach (from Low Earth Orbit to interplanetary) and in terms of the amount of data to transmit, new technologies need to be developed to provide adequate telecommunication support. This paper aims to review the telecommunication systems that have been developed at the Jet Propulsion Laboratory for some of the most recent CubeSat missions operating at different frequency bands: ASTERIA (S-Band), MarCO (X-Band and UHF) and ISARA (Ka-Band and UHF). For each of these missions: the telecommunication challenges and requirements are listed; the final system design is presented; the characteristics of the different hardware components are shown; and the lessons learned through operations are discussed.

Service productivity as mutual learning

2015 ◽  
Vol 7 (2/3) ◽  
pp. 296-311 ◽  
Author(s):  
Christian Grönroos ◽  
Katri Ojasalo
Keyword(s):  
Open Systems ◽  
Cost Savings ◽  
Service Organizations ◽  
Content Type ◽  
Mutual Learning ◽  
Context Learning ◽  
Starting Point ◽  
Service Production ◽  
Service Productivity ◽  
Internal Efficiency

Purpose – The purpose of this paper is to analyse the mutual learning implications for service productivity of the characteristics of service and service production. Design/methodology/approach – This is a conceptual paper. The starting point is, first of all, that productivity as a management concept should help a firm to manage its economic profit, and secondly, that service organizations are open systems, where the customers participate as co-producers and are exposed to the firm’s production resources and processes. Unlike in manufacturing, to understand productivity in service organizations as a means of managing profit, cost effects and revenue effects of changes in the productions system cannot be separated. Due to the interaction between customers and the firm’s resources during service production, dialogical collaboration between them develops. This enables mutual learning. Findings – Given the social dynamics in service production processes, four learning processes that influence service productivity are identified. Two processes enhance the organizations’s internal efficiency (cost savings), and two enhance its external effectiveness (perceived quality, revenue generation); two are organization-driven, two are customer-driven. Research limitations/implications – The mutual learning model demonstrates how the service provider by learning from the dynamics of service encounters in many ways can manage the productivity of the organizations’s processes. It shows that learning enables improvement of service productivity through effects enhancing both internal efficiency and external effectiveness. Originality/value – In a productivity context, learning has not earlier been studied as a mutual learning phenomenon.

Modeling multi-state system reliability analysis in a power station under fatal and nonfatal shocks: a simulation approach

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mohammad Reza Pourhassan ◽  
Sadigh Raissi ◽  
Arash Apornak
Keyword(s):  
Reliability Analysis ◽  
System Reliability ◽  
System Performance ◽  
Failure Process ◽  
State System ◽  
Failure Behavior ◽  
Simulation Approach ◽  
Critical System ◽  
Content Type ◽  
System Reliability Analysis

PurposeIn some environments, the failure rate of a system depends not only on time but also on the system condition, such as vibrational level, efficiency and the number of random shocks, each of which causes failure. In this situation, systems can keep working, though they fail gradually. So, the purpose of this paper is modeling multi-state system reliability analysis in capacitor bank under fatal and nonfatal shocks by a simulation approach.Design/methodology/approachIn some situations, there may be several levels of failure where the system performance diminishes gradually. However, if the level of failure is beyond a certain threshold, the system may stop working. Transition from one faulty stage to the next can lead the system to more rapid degradation. Thus, in failure analysis, the authors need to consider the transition rate from these stages in order to model the failure process.FindingsThis study aims to perform multi-state system reliability analysis in energy storage facilities of SAIPA Corporation. This is performed to extract a predictive model for failure behavior as well as to analyze the effect of shocks on deterioration. The results indicate that the reliability of the system improved by 6%.Originality/valueThe results of this study can provide more confidence for critical system designers who are engaged on the proper system performance beyond economic design.

A novel design space concept for design of concrete foundation supporting chemical reactors

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Osama Bedair
Keyword(s):  
Design Space ◽  
Cost Savings ◽  
Space Representation ◽  
Chemical Reactors ◽  
Content Type ◽  
Gas Recovery ◽  
Wide Range ◽  
Numerical Finite Element ◽  
Novel Concept ◽  
Reactor Models

PurposeThis paper presents a novel concept for design of concrete support system for chemical reactors used in refineries and petrochemical plants. Graphical method is described that can be used to size the concrete base and piling system. Recommendations are also provided to optimize the parameters required for the design. The procedure is illustrated for design of two reactor models commonly used in gas recovery units.Design/methodology/approachDesign space representation for the foundation system is described for chemical reactors with variable heights. The key points of the design graph are extracted from the numerical finite element models. The reactor load is idealized at discrete points to transfer the loads to the piles. Bilateral spring system is used to model the soil restrains.FindingsThe graphical approach is economical and provides the design engineer the flexibility to select the foundation parameters from wide range of options.Practical implicationsThe concept presented in the paper can be utilized by engineers in the industry for design of chemical reactors. It must be noted that little guidelines are currently available in practice addressing the structural design aspects.Originality/valueA novel concept is presented in this paper based on significant industrial design experience of reactor supports. Using the described method leads to significant cost savings in material quantity and engineering time.

A 12-pulse rectifier with passive harmonic reduction based on UIPT in more electric aircrafts

Circuit World ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Rohollah Abdollahi
Keyword(s):  
Power Factor ◽  
Harmonic Distortion ◽  
Cost Savings ◽  
Cost Effective ◽  
Industrial Applications ◽  
Input Current ◽  
New Combination ◽  
Content Type ◽  
Harmonic Reduction ◽  
Simulation Results

Purpose The purpose of this paper is to provide a T autotransformer based 12-pulse rectifier with passive harmonic reduction in more electric aircraft applications. The T autotransformer uses only two main windings which result in volume, space, size, weight and cost savings. Also, the proposed unconventional inter-phase transformer (UIPT) with a lower kVA rating (about 2.6% of the load power) compared to the conventional inter-phase transformer results in a more harmonic reduction. Design/methodology/approach To increase rating and reduce the cost and complexity of a multi-pulse rectifier, it is well known that the pulse number must be increased. In some practical cases, a 12-pulse rectifier (12PR) is suggested as a good solution considering its simple structure and low weight. But the 12PR cannot technically meet the standards of harmonic distortion requirements for some industrial applications, and therefore, they must be used with output filters. In this paper, a 12PR is suggested, which consists of a T autotransformer 12PR and a passive harmonic reduction (PHR) based on the UIPT at direct current (DC) link. Findings To show the advantage of this new combination over other solutions, simulation results are used, and then, a prototype is implemented to evaluate and verify the simulation results. The simulation and experimental test results show that the input current total harmonic distortion (THD) of the suggested 12PR with a PHR based on UIPT is less than 5%, which meets the IEEE 519 requirements. Also, it is shown that in comparison with other solutions, it is cost effective, and at the same time, its power factor is near unity, and its rating is 29.92% of the load rating. Therefore, it is obvious that the proposed rectifier is a practical solution for more electric aircrafts. Originality/value The contributions of this paper are summarized as follows. The suggested design uses a retrofit T autotransformer, which meets all technical constraints, and in comparison, with other options, has less rating, weight, volume and cost. In the suggested rectifier, a PHR based on UIPT at its dc link of 12PR is used, which has good technical capabilities and lower ratings. In the PHR based on UIPT, an IPT is used, which has an additional secondary winding and four diodes. This solution leads to a reduction in input current THD and conduction losses of diodes. In full load conditions, the input line current THD and power factor are 4% and 0.99, respectively. The THD is less than 5%, which satisfies IEEE-519 and DO-160G requirements.

The factors behind working in virtual community

2019 ◽  
Vol 12 (2) ◽  
pp. 246-267 ◽  
Author(s):  
Anitha Acharya
Keyword(s):  
Virtual Teams ◽  
Virtual Community ◽  
Cost Savings ◽  
Working Hours ◽  
Substantial Cost ◽  
Content Type ◽  
Part Time ◽  
Research Findings ◽  
Hourly Basis ◽  
Practical Implications

Purpose In this paper, the prior research on virtual teams was reviewed to assess the state of the literature. The purpose of this paper is to determine why individuals prefer working in virtual teams (also termed liquid workers and part-time workers). Previous researchers have focussed on the benefits that organizations receive if they hire liquid workers, but to date, no research has been conducted to determine the perspective of these liquid workers. The various definitions of virtual teams are discussed and an integrative definition is proposed that suggests all teams may be defined in terms of their extent of virtualness. Design/methodology approach A systematic review of the literature on virtual teams was conducted. The data were collected from 12 informants. A thematic analysis was used to analyse the data. Findings Six main themes were identified, namely, pliability, opportunities, increased earnings, vigour, family and transportation. Research limitations/implications This study was conducted in a three-metropolitan city in India and warrants being extended to rural and international settings to gain additional insights and confirmation of the research findings. Practical implications It is suggested that organizations who recruit liquid workers will be in a position for substantial cost savings; this is because organizations usually make payment of liquid workers’ wages on an hourly basis. This will help the organizations to schedule the number of working hours depending on their needs. Originality/value The current study is novel as there is a paucity of research in identifying the factors behind working in the virtual community in India. This study presents the first research of its kind to the best knowledge of the author, and the findings will be valuable for companies who are looking for cost savings.

scholarly journals Cultivate, assess, advocate, implement, and sustain

2017 ◽  
Vol 33 (2) ◽  
pp. 100-116 ◽  
Author(s):  
Sara Mannheimer ◽  
Conor Cote
Keyword(s):  
Cost Savings ◽  
Digital Preservation ◽  
Shared Vision ◽  
Limited Resources ◽  
Shared Knowledge ◽  
Collective Knowledge ◽  
Content Type ◽  
The Cost ◽  
Ongoing Support

Purpose For libraries with limited resources, digital preservation can seem like a daunting responsibility. Forming partnerships can help build collective knowledge and maximize combined resources to achieve digital preservation goals. This paper aims to provide guidance to help libraries with limited resources achieve digital preservation goals by forming partnerships to build collective knowledge and maximize combined resources. Design/methodology/approach In 2015, librarians from four Montana institutions formed the Digital Preservation Working Group (DPWG), a collaboration to increase digital preservation efforts statewide. The group’s immediate goals were to promote digital preservation best-practices at each individual institution, and to learn about and support each other’s work. The group’s long-term goal was to implement a shared digital preservation service that would fill gaps in existing digital preservation efforts. Findings Beyond the cost savings gained by sharing a digital preservation service, the members of DPWG benefitted from shared knowledge and expertise gained during the partnership. The group also functioned as a sounding board as each institution built its digital preservation program, and it became a system of support when challenges arose. Practical/implications This paper proposes a five-point plan for creating digital preservation partnerships: cultivate a foundation of knowledge and identify a shared vision; assess the current digital preservation landscape at each institution; advocate for the value of digital preservation activities; implement shared digital preservation services; and sustain group activities and establish structures for ongoing support. Originality/value The activities of DPWG provide a model for institutions seeking to collaborate to meet digital preservation challenges. This paper shows that by implementing a structured plan, institutions can build and sustain digital preservation partnerships, thus positioning themselves to achieve digital preservation success.

Importance measures for degrading components based on cooperative game theory

2019 ◽  
Vol 37 (2) ◽  
pp. 189-206
Author(s):  
Yingsai Cao ◽  
Sifeng Liu ◽  
Zhigeng Fang
Keyword(s):  
Cooperative Game ◽  
Shapley Value ◽  
System Reliability ◽  
Design Methodology ◽  
System Structure ◽  
Importance Measure ◽  
Engineering Systems ◽  
Content Type ◽  
Timely Feedback ◽  
Degradation Models

Purpose The purpose of this paper is to propose new importance measures for degrading components based on Shapley value, which can provide answers about how important players are to the whole cooperative game and what payoff each player can reasonably expect. Design/methodology/approach The proposed importance measure characterizes how a specific degrading component contributes to the degradation of system reliability by using Shapley value. Degradation models are also introduced to assess the reliability of degrading components. The reliability of system consisting independent degrading components is obtained by using structure functions, while reliability of system comprising correlated degrading components is evaluated with a multivariate distribution. Findings The ranking of degrading components according to the newly developed importance measure depends on the degradation parameters of components, system structure and parameters characterizing the association of components. Originality/value Considering the fact that reliability degradation of engineering systems and equipment are often attributed to the degradation of a particular or set of components that are characterized by degrading features. This paper proposes new importance measures for degrading components based on Shapley value to reflect the responsibility of each degrading component for the deterioration of system reliability. The results are also able to give timely feedback of the expected contribution of each degrading component to system reliability degradation.

scholarly journals Modelling the comparative costs of Namaste Care: results from the namaste care intervention UK study

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jennifer Bray ◽  
Dawn Brooker ◽  
Isabelle Latham ◽  
Darrin Baines
Keyword(s):  
Usual Care ◽  
Positive Impact ◽  
Cost Model ◽  
Well Being ◽  
Care Homes ◽  
Advanced Dementia ◽  
Content Type ◽  
Care Intervention ◽  
The Impact ◽  
Care Costs

Purpose The purpose of this paper is to populate a theoretical cost model with real-world data, calculating staffing, resource and consumable costs of delivering Namaste Care Intervention UK (NCI-UK) sessions versus “usual care” for care home residents with advanced dementia. Design/methodology/approach Data from five care homes delivering NCI-UK sessions populated the cost model to generate session- and resident-level costs. Comparator usual care costs were calculated based on expert opinion and observational data. Outcome data for residents assessed the impact of NCI-UK sessions and aligned with the resident-level costs of NCI-UK. Findings NCI-UK had a positive impact on residents’ physical, social and emotional well-being. An average NCI-UK group session cost £220.53, 22% more than usual care, and ran for 1.5–2 h per day for 4–9 residents. No additional staff were employed to deliver NCI-UK, but staff-resident ratios were higher during Namaste Care. Usual care costs were calculated for the same time period when no group activity was organised. The average cost per resident, per NCI-UK session was £38.01, £7.24 more than usual care. In reality, costs were offset by consumables and resources being available from stock within a home. Originality/value Activity costs are rarely calculated as the focus tends to be on impact and outcomes. This paper shows that, although not cost neutral as previously thought, NCI-UK is a low-cost way of improving the lives of people living with advanced dementia in care homes.

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